Question

Petrol and diesel can be obtained from:
A) Coal tar
B) Coal
C) Petroleum
D) Coal gas

Answer 1

We know that in organic chemistry, hydrocarbons are an important topic. The hydrocarbons are majorly classified as three groups. There are alkane, alkene and alkyne. The alkane means carbon-carbon single bond. The alkene has a carbon-carbon double bond. The alkyne means carbon-carbon having triple bond in the molecule. It has some general formulas. The general formula of alkane is ${{\text{C}}_{\text{n}}}{{\text{H}}_{{\text{2n + 2}}}}$. The general formula of alkene is ${{\text{C}}_{\text{n}}}{{\text{H}}_{{\text{2n}}}}$. The general formula of alkyne is ${{\text{C}}_{\text{n}}}{{\text{H}}_{{\text{2n - 2}}}}$. Coal tar is a mixture of various substances. Coal tar has some hydrocarbon molecules like alkane, alkene, alkyne and benzene related molecules. It also has some alcohol derived compounds also.

Complete answer:
Petrol and diesel can be obtained from coal tar.
Petrol and diesel can be obtained from petroleum.
Petrol and diesel can be obtained from coal gas.
According to the above discussion, we conclude Petrol and diesel can be obtained from coal tar, petroleum and coal gas.

Hence the options A, B and C all became the correct answer.

Note:
We have to know the conversion of one type of hydrocarbon to another hydrocarbon by oxidation and reduction. The oxidation of alkane to give alkene. The oxidation of alkene to give alkyne. The reduction of alkyne to give alkene. The reduction of alkene to give alkane. The oxidation means the addition of oxygen or removal of hydrogen or the loss of electrons in the reactant in chemical reaction. The reduction means the removal of hydrogen or the addition of oxygen or the gain of electrons in the chemical reaction. Phenol is one of the mono substituent benzene compounds. Each mono-substituent moiety has three named positions in the ring. In the ring nearby mono substituent group is called ortho position, that means two ortho positions are in the ring, because of the left and right side of the substituent group. The alternatively position of the substituent group in the ring is called meta position, here also two meta positions possible in the left and right side of the substituent group. Para position is nothing but directly opposite to the substituent group in the ring. Electrophilic substitutions are attacked in ortho and para position in the ring.